The present invention pertains to a process for recovering water from moist gas, e.g., moist atmospheric air by utilizing solar energy, an absorbing agent and a heat-accumulator which comprises conducting two air flows of differential temperature alternately through the water-absorbing agent and passing same through the heat-accumulator. The invention also pertains to a plant for carrying out the process.
Processes for drying air and other moist gases are known in the art. In these prior art processes, water vapor is condensed by refrigerators or absorbed by absorbing agents such as molecular sieves, activated carbon or silical gel.
Recently a process and a plant have been proposed for recovering water from moist air, wherein the moisture content in the air, which is cooled overnight, is absorbed by an absorbing agent, in particular silica gel of a special kind, while a heat-accumulator in the form of a layer of stones is cooled down simultaneously. During the day the silica gel is regenerated by the now warm air whereby the relative humidity of the air is increased to such an extent that when the air passes through the cold layer of stones, water is condensed on the surface of the stones. The condensed water flows in the form of drops or a film into the trough.
The above process is suited for being carried out especially at those places where the relative humidity is high and large differences in temperature occur.